The use of electronic communications is ubiquitous. Such communications commonly require the routing of electrical conductors between multiple locations in an article of manufacture. For example, in transportation applications, automobiles, ships, trains, airplanes, and other vehicles commonly bundle large numbers of conductors. These conductors are routed through various compartments in the vehicle, e.g., from a remote sensor to a central processor. While the use of external conductors is adequate for many applications, there are applications that can be problematic. For example, environmental exposure can cause corrosion and other degradation of the conductors which can in turn lead to communication loss. Deployment of conductor bundles in close proximity to moving parts can also be problematic as the conductors may inadvertently engage the moving parts.
Typical petroleum drilling operations employ a number of techniques to gather information about the borehole and the formation through which it is drilled. Such techniques are commonly referred to in the art as measurement while drilling (MWD) and logging while drilling (LWD). Transmission of data from a downhole tool to the surface is a difficulty common to many drilling operations. Data are commonly transmitted to the surface via encoded pressure pulses in a column of drilling fluid. While such ‘mud pulse telemetry’ techniques have long been commercially serviceable, they are also severely bandwidth limited (a typical mud pulse channel has a bandwidth on the order of about 1 to 20 bits per second).
In recent years, Intelliserv® has introduced a ‘wired pipe’ concept (referred to as Intellipipe®) in which the drill string is outfitted with a wire that enables high-speed two-way communication between the bottom hole assembly (BHA) and the surface (see for example U.S. Pat. No. 6,670,880). Proliferation of this technology has required downhole tool manufacturers to adapt their tools to accommodate the routing of an electrical conductor (e.g., a coaxial cable) through the length of the tool so as to be compatible with the wired drill pipe of Intelliserv®.
One technique that has been utilized is gun drilling a longitudinal bore through the entire length of the steel (or high strength steel) outer body of the tool. This process is both expensive and time consuming. Moreover, ensuring accurate placement of the bore along the entire length of the tool can be particularly problematic, especially in longer tools. Errors in the gun drilling process can significantly increase scrap rates during machining of the outer body portion of the tool. These increased scrap rates further increase the expense of the tool.
Therefore a need exists to be able to create a wire or cable channel in various articles of manufacture, for example, including vehicle bodies or frames. There is also a need to more quickly and inexpensively create a wire or cable channel in downhole tools in order to be compatible with wired drill pipe products. Additionally, there is a need to be able to create such channels without the need to appreciably alter the design of the existing tools.